Line Of Duty welcomed back yet more faces from its complicated past as it staged its most explosive episode of the series so far on Sunday night. 

The reappearances of slimy solicitor Jimmy Lakewell and OCG member Lee Banks have left us all with a lot of burning questions about what happens next, but in case you are in need of a refresher about where the returning characters fit into the larger picture, allow us to explain…

Who is Lee Banks?

Lee Banks – played by Alastair Natkiel – was first introduced in Line Of Duty in the fifth series as a member of the organised crime group. 

He worked with Lisa McQueen, Miroslav Minkowicz, Ryan Pilkington and John Corbett, the undercover officer who was embedded in the OCG. 

He is also a long-time associate of Robert Denmoor, who you might recall was one of the ‘Balaclava Men’ who were investigated in Operation Trapdoor back in series four. Denmoor was shot dead by Hastings during DC Jamie Desford’s hold up of AC-12 HQ. 

During his time on the outside, Banks kidnapped AC-12’s PC Maneet Bindra as the OCG sought to coerce her into working for them, before they later murdered her. 

Banks was arrested after he visited the home of bent officer Sergeant Jane Cafferty, who was being paid off for her part in helping coordinate the hijacking of a police convoy transporting seized drugs. 

After being sent to Blackthorn prison, Banks was visited by Superintendent Ted Hastings, where the pair had a conversation that viewers were not privy to. 

This point was central to one of the loose ends the series five finale didn’t tie up, as there were questions about whether Hastings had leaked information about Corbett’s real identity to Banks, which ultimately led to Corbett’s death. 

Under questioning, Hastings lied about ever visiting Banks, but AC-3 boss DCS Patricia Carmichael was still convinced he’d blown Corbett’s cover. She was unable to prove it when DCC Wise insisted the case against Hastings was shut down.

Hastings was seemingly in the clear when McQueen also said that Banks had only informed the OCG that there was a rat inside the unit, and not who the information came from. However, it could still be that Banks did not tell McQueen that his source was Hastings. 

Upon his return to the show, we saw Banks murder Jimmy Lakewell in his cell with the co-operation of DSU Ian Buckells. This was seemingly on the orders of the OCG, who believed he had leaked information to the police that would have helped in the investigation into journalist Gail Vella’s murder. 

How could Banks’ return be significant?

Banks’ reappearance could suggest that Hastings’ conduct – and his mysterious relationship with Corbett’s widow Steph – will be further explored. 

We also haven’t forgotten that he shares the same surname as Carl Banks, one of the prime suspects in Vella’s murder, either. 

Who is James ‘Jimmy’ Lakewell?

Jimmy Lakewell – played by former star of The Office, Patrick Baladi – featured in series four of Line Of Duty as founding partner of the criminal law firm Lakewell, Dean & Stevenson, and was a university friend of antagonist DCI Roz Huntley’s husband Nick. 

Lakewell was in league with organised crime and was part of a cover up in Operation Trapdoor, which looked into the kidnapping and murder of Baswinder Kaur, the disappearance of Leonie Collersdale and the attempted kidnapping of Hana Reznikova.

He was also responsible for instructing one of the so-called ‘Balaclava Men’ to intercept DS Steve Arnott when he arrived at the Lakewell, Dean & Stevenson offices, which ended up with him being pushed down the stairs and sustaining injuries that have subsequently seen him develop an addiction to painkillers. 

Lakewell represented DCI Huntley in her final interrogation with AC-12, where she admitted to killing forensic investigator Tim Ifield. She then turned the tables on Lakewell and revealed that he had planted evidence to frame Michael Farmer for the crimes investigated by Operation Trapdoor. In league with ACC Derek Hilton and organised crime, he was part of a scheme where vulnerable police staff were pressured to manipulate evidence.

At the end of series four, Lakewell pleaded guilty to perverting the course of justice, but declined witness protection and refused to testify and was sent to prison. 

Many viewers correctly predicted his return to the show earlier in the series when a recording from Vella’s computer revealed a man speaking to her about police corruption. 

We have now seen that AC-12 have obtained a full version of this recording, in which Lakewell revealed to Vella details of another case of police corruption that had a racist element. Arnott, Hastings and Bishop deduced this must have been the case Vella had subsequently tried to investigate and likely led to her death.  

After hinting he was being threatened into silence by corrupt prison officers, AC-12 came up with a plan to break Lakewell out and interview him about the case, but the OCG ambushed the convoy in an attempt to kill him. 

While he survived, Lakewell remained silent during a later interview with AC-12 and refused witness protection, asking to return to prison. 

He was subsequently killed by Lee Banks, in collusion with Buckells upon his return to HMP Blackthorn. 

However, there was a suggestion he had actually filled Arnott in on the details about his interview with Vella during a conversation we didn’t get to see on screen, so Lakewell’s death doesn’t necessarily mean AC-12’s lead has gone cold.

Line Of Duty continues on Sunday at 9pm on BBC One.